Washington University proposes to establish the Data Coordinating Center (DCC) for the Polycystic Kidney Disease Treatment Network (PKD-TN) within the Division of Biostatistics. WU performs a similar function for the NIDDK-sponsored CRISP study that is developing imaging parameters to follow the progression of Polycystic Kidney Disease (PKD). WU generally, and this investigative team specifically, has a strong record of experience as the DCC for multicenter studies. The DCC will participate as a key member of the Steering Committee, taking a leadership role in planning the studies, leading the statistical analyses and reporting of these studies. A web-based data entry system, based on the one currently being used for CRISP, will be customized for the needs of the PKD-TN. The DCC will serve as the communications hub for the PKD-TN, arranging meetings, telephone and electronic communications and producing and archiving study-related documents. A three-group, double-masked, randomized, multicenter, placebo-controlled trial will address whether either an ACE inhibitor or an angiotensenin 2 antangonist will retard the progression of renal impairment in PKD. The trial will enroll 1,800 PKD subjects with a wide range of renal function and follow them for 3-5 years. The primary endpoint will be that of time to death, ESRD or a doubling of the serum creatinine level. GFR levels will be assessed annually with a central laboratory and will be used as a secondary endpoint. The GFR measurements will allow us to address questions about variations in treatment effect according to the severity of renal impairment and the presence of common features of the disease such as hypertension and proteinuria. Blood and urine samples will be collected at baseline and annually and stored in the NIDDK's repository for future pharmocogenitic studies and future studies of biomarkers of the progression of PKD. An early Phase II trial of BMP-7, a cytokine which has an essential role in coordinating the formation of the emerging metanephos, is proposed. BMP-7 has been shown to maintain renal function in animal models with acute and chronic renal disease and to reduce renal hypertrophy. A simple, two-group, placebo controlled, randomized clinical trial will be conducted to determine whether BMP-7 can retard the growth rate of the kidneys in PKD subjects. MRI-based imaging will be used to measure kidney size for the trial.